CN105388415B - Circuit breaker on-off TRV capability evaluation method based on two-segment time scale - Google Patents

Abstract

The present invention provides a method for evaluating the TRV breaking ability of a circuit breaker based on a two-stage time scale, which includes the following steps: collecting the short-circuit current power frequency effective value of the short-circuit current flowing through the circuit breaker when a short-circuit fault occurs in the area of the line equipped with a series compensation device ; Collect the circuit breaker TRV on the line with series compensation device; analyze the circuit breaker TRV characteristic parameters before and after the peak time of circuit breaker TRV respectively; The present invention covers the whole time process of breaking the TRV of the circuit breaker, and clarifies the specific evaluation basis, conducts a comprehensive evaluation of the breaking TRV capability of the circuit breaker, and provides an all-round and more reliable technical basis for accurately evaluating the breaking TRV capability of the circuit breaker equipment. Ensure the safety of circuit breaker equipment.

Description

A Method for Evaluation of Circuit Breaker Breaking TRV Capability Based on Two-stage Time Scale

technical field

The invention relates to an evaluation method, in particular to a method for evaluating the breaking TRV capability of a circuit breaker based on a two-stage time scale.

Background technique

The circuit breaker is one of the important devices in the AC power grid, and it is one of the basic functions of the circuit breaker to reliably break the intra-area short-circuit fault of the line. During the short-circuit fault process in which the circuit breaker breaks the line, whether the short-circuit current AC arc can be extinguished after zero crossing depends on the recovery process of the dielectric insulation of the arc gap and the voltage recovery process of the arc gap. It is particularly important to analyze the voltage recovery process when the circuit breaker opens and short-circuits. After the circuit breaker is extinguished, the voltage with transient characteristics that first appears in the arc gap is called the transient recovery voltage (Transient Recovery Voltage, TRV). From the perspective of arc extinguishing, the transient recovery voltage has decisive significance when breaking a short-circuit fault. TRV mainly evaluates two indicators, one is the rate of rise of recovery voltage (RRRV for short), and the other is the peak value. In addition, the steady-state breaking short-circuit current level corresponding to when the circuit breaker breaks TRV is also an important influencing factor .

The circuit breaker TRV is the difference between the overvoltage on both sides of the circuit breaker to the ground. After the line is equipped with a series compensation device, when a fault occurs on the line, the short-circuit current flows through the series compensation device to cause an overvoltage at both ends of the series compensation device, which is superimposed on the open circuit The overvoltage on the line side of the circuit breaker to the ground, and the installation of a series compensation device on the line will increase the short-circuit current of the system. When the line fails, it will also increase the overvoltage on the bus side of the circuit breaker. The superposition of the two will cause the circuit breaker to trip when the fault is cleared. The difference between the voltages on both sides of the fracture, that is, TRV, has an influence, and the degree of influence depends on the action results of the overvoltage protection measures of the series compensation device and the linkage measures.

The overvoltage protection measures of the series compensation device are as follows: when a short-circuit fault occurs in the line (the fault occurs between the circuit breakers on both sides of the line where the series compensation device is located), the series compensation device is allowed to be bypassed. When the metal oxide voltage limiter When the (MOV) current and energy consumption reach the set value, the control system will issue a spark gap bypass trigger command, and at the same time command the bypass switch to close, bypassing the series compensation device and MOV.

The linkage measures of the series compensation device are as follows: when a short-circuit fault occurs in the line on which the series compensation device is installed, the relay protection system on both sides of the line will start the fast bypass of the capacitor bank of the phase ( spark gap action, and at the same time command the bypass switch to close), in order to realize the linkage of circuit breaker and capacitor spark gap.

In comparison, the spark gap action is fast (conduction within 40ms after the line fault), and the bypass switch action is slow (closed after 70ms after the line fault). If the capacitor bank is bypassed by the spark gap action, it can be used in circuit breakers. Before tripping (about 50ms after the line fault), the bypass is realized. If the spark gap does not act and the capacitor bank is bypassed only by closing the bypass switch, it will only realize the bypass after the circuit breaker trips.

When a short-circuit fault occurs in the line equipped with a series compensation device, if the short-circuit current flowing through the series compensation device is large, according to the overvoltage protection strategy of the series compensation device, the MOV current or energy consumption of the series compensation device will reach the protection setting value , and quickly bypass the capacitor bank by turning on the spark gap (close the bypass switch at the same time), because the spark gap action time is short (conduction within 40ms after the line fault), so it can be before the circuit breaker trips (40~ after the line fault) 50ms), that is, the capacitor bank is bypassed before TRV occurs, which can eliminate the influence of capacitor residual voltage on TRV, so that the TRV of the circuit breaker can be close to that without series compensation device; if the short-circuit current flowing through the series compensation device is relatively small Small, MOV current and energy consumption are relatively small, lower than its overvoltage protection setting value, the spark gap of the series compensation device does not operate, and the capacitor bank is not bypassed before the circuit breaker trips, due to the residual voltage of the capacitor bank, When the line circuit breaker trips, its fracture TRV will increase, which may affect the normal breaking of the circuit breaker. When taking linkage measures, the capacitor bank is bypassed by closing the line protection linkage bypass switch. The bypass switch acts slowly (closed after 70ms after the line fault), so it will bypass the capacitor bank after the circuit breaker trips. The residual voltage of the group will affect the TRV of the circuit breaker.

At present, the TRV breaking capability of circuit breakers is mainly evaluated based on the expected TRV parameters stipulated in the existing EHV and UHV AC circuit breaker standards. The national standards adopted are: GB1984-2014 "High Voltage AC Circuit Breakers", GB/Z 24838-2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breakers".

The TRV parameter levels for 126kV ~ 1100kV circuit breaker breaking in the existing national standards are as follows:

TRV peak range is 144～2245kVpeak (1.8～2.5pu, U _r is the rated voltage of the circuit breaker), the duration to reach the peak value is 33~3500μs, and the RRRV is 1.54~7kV/μs.

Contents of the invention

Aiming at the disadvantage that the existing technology cannot correctly evaluate the ability of the circuit breaker to break the maximum peak time delay TRV, the present invention provides a method for evaluating the ability of the circuit breaker to break the TRV based on the two-stage time scale, covering the ability of the circuit breaker to break The full-time process of TRV, and the specific evaluation basis are clearly defined, and the TRV breaking ability of the circuit breaker is comprehensively evaluated, which provides a comprehensive and more reliable technical basis for accurately evaluating the breaking TRV ability of the circuit breaker equipment, and ensures the safety of the circuit breaker equipment.

In order to realize the above-mentioned purpose of the invention, the present invention takes the following technical solutions:

The present invention provides a method for evaluating the TRV capability of a circuit breaker based on a two-stage time scale. The evaluation method includes the following steps:

Step 1: Collect the power frequency effective value of the short-circuit current flowing through the circuit breaker when a short-circuit fault occurs in the line equipped with a series compensation device;

Step 2: collect the TRV of the circuit breaker on the line with the series compensation device installed;

Step 3: Analyze the TRV characteristic parameters of the circuit breaker before and after the peak time of the circuit breaker TRV;

Step 4: Evaluate the breaking capability of the circuit breaker on the TRV using a two-stage time scale.

In the step 1, the acquisition of the power frequency effective value of the short-circuit current flowing through the circuit breaker when an internal short-circuit fault occurs on the line equipped with a series compensation device is completed through electromagnetic transient simulation software simulation or AC electrical quantity test.

In the step 2, through electromagnetic transient simulation software simulation or high-frequency overvoltage test, the collection of circuit breaker TRV on the line equipped with series compensation device is completed.

In the step 3, the TRV characteristic parameters of the circuit breaker before and after the peak time of the circuit breaker TRV are analyzed respectively with the peak time T1 _of the circuit breaker TRV in the national standard as the limit;

The characteristic parameters of circuit breaker TRV include peak value, rising rate and time to peak value of circuit breaker TRV.

The method for evaluating the breaking TRV capability of a circuit breaker based on a two-stage time scale according to claim 1, characterized in that: in the step 3, for different voltage levels, national standards are used to determine the peak time of the circuit breaker TRV, specifically Yes: For circuit breakers with a voltage level of 126kV ~ 1100kV, the national standards adopted are GB1984-2014 "High Voltage AC Circuit Breakers" and GB/Z 24838-2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breakers", different circuit breaker TRV test methods Next, the range of the breaker TRV peak time is 33 ~ 3500μs.

Described step 4 specifically comprises the following steps:

Step 4-1: The time when the circuit breaker TRV reaches the peak value is represented by T ₁ , and the time 20ms after the circuit breaker is disconnected is represented by T _2. The time from the time when the circuit breaker TRV appears to the time when the circuit breaker TRV reaches the peak value is set as the first stage, that is, 0 -T ₁ ; set the time from the peak time of the circuit breaker TRV to 20ms after the circuit breaker is disconnected as the second stage, that is, T ₁ -T ₂ ;

Step 4-2: Evaluate the TRV breaking capability of the circuit breaker in the first stage and the second stage respectively;

Step 4-3: Conduct a comprehensive evaluation of the circuit breaker's ability to break the TRV.

Said step 4-2 comprises the following steps:

Step 4-2-1: Evaluate the TRV breaking ability of the circuit breaker in the first stage, and obtain the evaluation result of the breaking TRV ability of the circuit breaker in the first stage; specifically:

According to the distance from the location of the short-circuit fault in the line with the series compensation device to the circuit breaker, and the collected short-circuit current power frequency effective value of the short-circuit current flowing through the circuit breaker when the short-circuit fault occurs in the line with the series compensation device, According to the TRV test method specified in GB1984-2014 "High Voltage AC Circuit Breaker" and GB/Z 24838-2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breaker", when the absolute value of the peak value of the TRV of the circuit breaker and the absolute value of the rate of rise of the TRV of the circuit breaker When none of them is higher than the corresponding specified value in the national standard, it is considered that the TRV of the circuit breaker does not exceed the standard, that is, the breaking TRV capacity of the circuit breaker meets the requirements of the first stage; otherwise, the absolute value of the peak value of the TRV of the circuit breaker or the rising rate of the TRV When any of the absolute values is higher than the corresponding specified value in the national standard, it is considered that the TRV of the circuit breaker exceeds the standard, that is, the breaking TRV capability of the circuit breaker does not meet the requirements of the first stage;

Step 4-2-2: Evaluate the TRV breaking ability of the circuit breaker in the second stage, and obtain the evaluation result of the breaking TRV ability of the circuit breaker in the second stage; the details include:

Compare the absolute value of the TRV peak value of the circuit breaker with GB/T 11022-2011 "GB/T 11022-2011 Common Technical Requirements for High Voltage Switchgear and Control Equipment Standards" and GB/Z 24838-2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breakers" The rated operating impulse withstand voltage of the circuit breaker fracture specified in the national standard, when the absolute value of the peak value of the circuit breaker TRV is not higher than the rated operating impulse withstand voltage of the circuit breaker fracture specified in the national standard, it is considered that the circuit breaker TRV does not exceed the standard, that is, the circuit breaker The breaking TRV capability of the circuit breaker meets the requirements of the second stage; otherwise, it is considered that the TRV of the circuit breaker exceeds the standard, that is, the breaking TRV capability of the circuit breaker does not meet the requirements of the second stage.

In the step 4-3, the TRV breaking capability evaluation results of the circuit breaker in the first stage and the TRV breaking ability evaluation results of the circuit breaker in the second stage are integrated according to the logical AND relationship, that is, the TRV breaking ability of the circuit breaker meets the requirements of the first stage , and meet the requirements of the second stage at the same time, it means that the breaking ability of the circuit breaker to break TRV meets the requirements.

Compared with the closest prior art, the technical solution provided by the present invention has the following beneficial effects:

The present invention proposes a method for evaluating the breaking TRV capability of a circuit breaker based on a two-stage time scale, aiming at the possibility that there may be _a delay between the break TRV peak time when the circuit breaker clears the fault and the circuit breaker TRV arrival peak time T1 stipulated by the national standard The problem is that according to the characteristics of TRV characteristic parameters similar to the national standard operating impulse voltage waveform, the breaking TRV capability of the circuit breaker is evaluated by dividing the two time scales before and after the breaker TRV peak time stipulated by the national standard, and the The time limits of the two time scales and the corresponding TRV evaluation criteria can cover the entire time course of the circuit breaker breaking TRV, and realize a comprehensive evaluation of the breaking TRV capability of the circuit breaker, which can significantly improve the evaluation of the breaking TRV ability of the circuit breaker Accuracy, and can be applied to AC circuit breakers with a voltage level of 126kV and above, covering the situation of adding or not adding series compensation to the line, and can provide more scientific technical means to ensure the safety of circuit breaker equipment, with a wide range of applications and applications bright future.

Description of drawings

Fig. 1 is a flow chart of a method for evaluating a circuit breaker's breaking TRV capability based on a two-stage time scale in an embodiment of the present invention;

Fig. 2 is a typical double-ended 1000kV power transmission system structural diagram in the embodiment of the present invention;

Fig. 3 is a TRV simulation waveform diagram corresponding to the maximum peak value when the circuit breaker clears the three-phase ground fault when no linkage measures are taken in the embodiment of the present invention;

Fig. 4 is a TRV simulation waveform diagram corresponding to the maximum peak value when the circuit breaker clears the three-phase ground fault before and after the linkage measures are taken in the embodiment of the present invention;

5 is a simulation waveform diagram of the circuit breaker current when the circuit breaker clears the three-phase ground fault before and after the linkage measures are taken in the embodiment of the present invention;

6 is a simulation waveform diagram of the voltage across the capacitor of the series compensation device when the circuit breaker clears the three-phase ground fault after the linkage measures are taken in the embodiment of the present invention;

7 is a simulation waveform diagram of the spark gap current of the series compensation device when the circuit breaker clears the three-phase ground fault after the linkage measures are taken in the embodiment of the present invention;

8 is a simulation waveform diagram of the bypass switch current of the series compensation device when the circuit breaker clears the three-phase ground fault after the linkage measures are taken in the embodiment of the present invention;

Fig. 9 is a simulated waveform diagram of the voltage on both sides of the circuit breaker when the circuit breaker clears the three-phase ground fault after the linkage measures are taken in the embodiment of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

In the present invention, when the conventional linkage bypass series compensation measures are taken after the series compensation device is installed on the AC line, the time when the maximum peak value of the fracture TRV when the circuit breaker clears the fault is the same as that of the existing GB1984-2014 "High Voltage AC Circuit Breaker", GB/Z24838 -2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breakers" national standard stipulates that there is a delay in the breaker TRV peak occurrence time (t2 or t3), and it is proposed to divide the peak occurrence time after the zero-crossing breaker specified in the standard into two The method of evaluating the breaking TRV capability of a circuit breaker based on the time scale, and according to the similar characteristics of the TRV waveform parameters and the standard operating impulse voltage waveform, it is clear that the TRV evaluation basis of the two time scales is the expected TRV opening in the existing circuit breaker standards. Break test parameters and fracture rated operating impulse withstand voltage parameters.

The present invention includes two time scales, covering the entire time course after the circuit breaker is disconnected, and can evaluate the ability of the line circuit breaker to interrupt TRV in the whole process of adding a series compensation device, thereby improving the accuracy of evaluating the circuit breaker's ability to interrupt TRV , and can be applied to AC circuit breakers with a voltage level of 126kV and above, covering the situation of adding or not installing a series compensation device on the line, which can effectively improve the safety of the circuit breaker, and has a wide range of applications and broad application prospects.

As shown in Figure 1, the present invention provides a method for evaluating the ability of a circuit breaker to break a TRV based on a two-stage time scale, and the evaluation method includes the following steps:

Step 1: Collect the power frequency effective value of the short-circuit current flowing through the circuit breaker when a short-circuit fault occurs in the line equipped with a series compensation device;

Step 2: collect the TRV of the circuit breaker on the line with the series compensation device installed;

Step 3: Analyze the TRV characteristic parameters of the circuit breaker before and after the peak time of the circuit breaker TRV;

Step 4: Evaluate the breaking capability of the circuit breaker on the TRV using a two-stage time scale.

In the step 1, the acquisition of the power frequency effective value of the short-circuit current flowing through the circuit breaker when an internal short-circuit fault occurs on the line equipped with a series compensation device is completed through electromagnetic transient simulation software simulation or AC electrical quantity test.

In the step 2, through electromagnetic transient simulation software simulation or high-frequency overvoltage test, the collection of circuit breaker TRV on the line equipped with series compensation device is completed.

In the step 3, the TRV characteristic parameters of the circuit breaker before and after the peak time of the circuit breaker TRV are analyzed respectively with the peak time T1 _of the circuit breaker TRV in the national standard as the limit;

The characteristic parameters of circuit breaker TRV include peak value, rising rate and time to peak value of circuit breaker TRV.

The method for evaluating the breaking TRV capability of a circuit breaker based on a two-stage time scale according to claim 1, characterized in that: in the step 3, for different voltage levels, national standards are used to determine the peak time of the circuit breaker TRV, specifically Yes: For circuit breakers with a voltage level of 126kV ~ 1100kV, the national standards adopted are GB1984-2014 "High Voltage AC Circuit Breakers" and GB/Z 24838-2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breakers", different circuit breaker TRV test methods Next, the range of the breaker TRV peak time is 33 ~ 3500μs.

Described step 4 specifically comprises the following steps:

Step 4-1: The time when the circuit breaker TRV reaches the peak value is represented by T ₁ , and the time 20ms after the circuit breaker is disconnected is represented by T _2. The time from the time when the circuit breaker TRV appears to the time when the circuit breaker TRV reaches the peak value is set as the first stage, that is, 0 -T ₁ ; set the time from the peak time of the circuit breaker TRV to 20ms after the circuit breaker is disconnected as the second stage, that is, T ₁ -T ₂ ;

Step 4-2: Evaluate the TRV breaking capability of the circuit breaker in the first stage and the second stage respectively;

Step 4-3: Conduct a comprehensive evaluation of the circuit breaker's ability to break the TRV.

Said step 4-2 comprises the following steps:

Step 4-2-1: Evaluate the TRV breaking ability of the circuit breaker in the first stage, and obtain the evaluation result of the breaking TRV ability of the circuit breaker in the first stage; specifically:

According to the distance from the location of the short-circuit fault in the line with the series compensation device to the circuit breaker, and the collected short-circuit current power frequency effective value of the short-circuit current flowing through the circuit breaker when the short-circuit fault occurs in the line with the series compensation device, According to the TRV test method specified in GB1984-2014 "High Voltage AC Circuit Breaker" and GB/Z 24838-2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breaker", when the absolute value of the peak value of the TRV of the circuit breaker and the absolute value of the rate of rise of the TRV of the circuit breaker When none of them is higher than the corresponding specified value in the national standard, it is considered that the TRV of the circuit breaker does not exceed the standard, that is, the breaking TRV capacity of the circuit breaker meets the requirements of the first stage; otherwise, the absolute value of the peak value of the TRV of the circuit breaker or the rising rate of the TRV When any of the absolute values is higher than the corresponding specified value in the national standard, it is considered that the TRV of the circuit breaker exceeds the standard, that is, the breaking TRV capability of the circuit breaker does not meet the requirements of the first stage;

Step 4-2-2: Evaluate the TRV breaking ability of the circuit breaker in the second stage, and obtain the evaluation result of the breaking TRV ability of the circuit breaker in the second stage; the details include:

Compare the absolute value of the TRV peak value of the circuit breaker with GB/T 11022-2011 "GB/T 11022-2011 Common Technical Requirements for High Voltage Switchgear and Control Equipment Standards" and GB/Z 24838-2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breakers" The rated operating impulse withstand voltage of the circuit breaker fracture specified in the national standard, when the absolute value of the peak value of the circuit breaker TRV is not higher than the rated operating impulse withstand voltage of the circuit breaker fracture specified in the national standard, it is considered that the circuit breaker TRV does not exceed the standard, that is, the circuit breaker The breaking TRV capability of the circuit breaker meets the requirements of the second stage; otherwise, it is considered that the TRV of the circuit breaker exceeds the standard, that is, the breaking TRV capability of the circuit breaker does not meet the requirements of the second stage.

In the step 4-3, the TRV breaking capability evaluation results of the circuit breaker in the first stage and the TRV breaking ability evaluation results of the circuit breaker in the second stage are integrated according to the logical AND relationship, that is, the TRV breaking ability of the circuit breaker meets the requirements of the first stage , and meet the requirements of the second stage at the same time, it means that the breaking ability of the circuit breaker to break TRV meets the requirements.

Example

For the 1000kV line close to the 3LG fault condition in the line side of the series compensation device of station B, calculate the circuit breaker clearing the 3LG (three-phase ground fault ) when the typical simulation waveform of TRV (as shown in Fig. 2 and Fig. 3), compare and analyze the evaluation effect of the circuit breaker TRV evaluation method proposed by the present invention on the breaking capacity of the circuit breaker.

In the typical simulation system shown in Figure 2, the line is a 490km 1000kV double-circuit transmission line on the same tower. A set of high-voltage shunt reactors with a rated capacity of 1200Mvar is installed at the head end of each line, and a set of rated capacity is installed at the end of the line. 960Mvar high-voltage shunt reactor; each circuit is equipped with a series compensation device with a compensation degree of 70%, and is scattered on both sides of the line, and the compensation degree of each side of the series compensation device is 35%.

Under the working conditions studied, if the line protection linkage bypass series compensation device measures are not taken, when a three-phase ground fault (3LG) occurs on the 1000kV line between Station A and Station B, the typical TRV waveform when the circuit breaker trips to clear the fault is shown in Figure 3 As shown, appear on the A phase circuit breaker. The maximum TRV peak value of the TRV waveform shown in Figure 3 is 2865kVpeak, and the corresponding TRV waveform rise rate and short-circuit current power frequency effective value are 1.34kV/μs and 3.3kArms respectively. The maximum TRV peak value appears at the first peak of the TRV waveform, and TRV The time T _p for the waveform to reach the peak value is 2.4ms, that is, the maximum TRV peak time is 2.4ms after the circuit breaker is opened.

As shown in Figure 4-9, when the line protection linkage bypass series compensation device is adopted, a 3LG fault occurs on the line. The gap is not conducting, and the phase series compensation device is bypassed only by closing the bypass switch. The bypass time is about 13.6ms later than that of the circuit breaker. The direction and the voltage on the bus side of the circuit breaker are reversed, so that the maximum peak value of its TRV appears at 13.6ms after the current of the A-phase circuit breaker crosses zero, which is the second valley of the TRV waveform, and the peak value is 2746kVpeak, which is higher than that without linkage bypass measures It corresponds to 2331kVpeak in the same time period; the maximum peak value of TRV is 944kVpeak within 3.5ms after the current of the A-phase circuit breaker breaks at zero crossing, which is significantly lower than the 2865kVpeak in the same time period without linkage, and the corresponding RRRV is 0.52kV/μs, which is also lower than the result without linkage.

For the 1100kV circuit breaker, according to the GB1984-2014 and GB/Z 24838-2009 national standards adopted by the technical solution of the present invention, under the condition that the circuit breaker is not equipped with an opening resistor, and under different test methods, the time range for the circuit breaker to reach the peak value of TRV is 271 ~3500μs.

As shown in Figure 4-9, according to the TRV evaluation method proposed by the technical solution of the present invention:

(1) The line fault point is located on the side of the series compensation line of station B. For the circuit breaker of station A, it is a remote fault. The simulation calculation shows that the effective value of the power frequency of the short-circuit current flowing through the circuit breaker of station A after the line fault is 3.3kArms , according to the OP1-OP2 (reverse breaking) test method in GB1984-2014 "High Voltage AC Circuit Breaker" and GB/Z 24838-2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breaker", the duration of TRV reaching the peak value It is 1752～3500μs.

(2) Taking 3500μs after the circuit breaker is broken as the boundary, it is divided into stage 1 and stage 2, and the key characteristics of the TRV waveform, such as the peak value and rising rate, are respectively taken when the line protection linkage bypass series compensation measures are not taken and taken under the working conditions parameters to analyze.

When no linkage measures are taken, the maximum peak value of TRV in stage 1, that is, within 0-3.5ms after the circuit breaker is disconnected, is 2865kVpeak, corresponding to RRRV of 1.34kV/μs, and the peak value exceeds the national standards of GB1984-2014 and GB/Z 24838-2009 The specified OP1-OP2 test method corresponds to the 2245kVpeak level and the 2610kVpeak level in the UHV circuit breaker breaking test. Therefore, the breaking TRV capability of the existing 1100kV circuit breaker in stage 1 does not meet the requirements; The maximum peak value within 3.5ms～20ms is 2331kV, which is lower than GB/T 11022-2011 "GB/T 11022-2011 Common Technical Requirements for High Voltage Switchgear and Control Equipment Standards", GB/Z 24838-2009 "1100kV High Voltage AC Open Circuit The rated operating impulse withstand voltage of the circuit breaker fracture specified in the national standard of "Technical Specifications for Circuit Breakers" is 2575kVpeak, so the breaking TRV capacity of the existing 1100kV circuit breakers in stage 2 can meet the requirements. According to the comprehensive analysis of the two stages, the TRV under the condition of not taking measures does not meet the breaking requirements of the circuit breaker.

When the linkage measures are taken, the maximum TRV peak value of the TRV within 0-3.5ms after the circuit breaker is disconnected in stage 1 is 944kV, and the corresponding RRRV is 0.52kV/μs, which are respectively lower than the national standards of GB1984-2014 and GB/Z 24838-2009 The specified OP1-OP2 test method corresponds to 2245kVpeak and 1.54kV/μs, so the TRV breaking capacity of the existing 1100kV circuit breaker in stage 1 can meet the requirements; The peak value is 2746kV, which exceeds the rated operating impulse withstand voltage of the circuit breaker fracture of 2575kVpeak specified in the national standards GB/T 11022-2011 and GB/Z 24838-2009. Therefore, the TRV breaking capacity of the existing 1100kV circuit breaker in stage 2 does not meet the requirements Require. According to the comprehensive analysis of the two stages, the TRV under the condition of taking linkage measures does not meet the breaking requirements of the circuit breaker.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Those of ordinary skill in the art can still modify or equivalently replace the specific implementation methods of the present invention with reference to the above embodiments. Any modifications or equivalent replacements departing from the spirit and scope of the present invention are within the protection scope of the claims of the pending application of the present invention.

Claims (5)

1. A circuit breaker breaking TRV capability evaluation method based on two-stage time scale, it is characterized in that: described evaluation method comprises the following steps: Step 1: Collect the power frequency effective value of the short-circuit current flowing through the circuit breaker when a short-circuit fault occurs in the line equipped with a series compensation device; Step 2: collect the TRV of the circuit breaker on the line with the series compensation device installed; Step 3: Analyze the TRV characteristic parameters of the circuit breaker before and after the peak time of the circuit breaker TRV; Step 4: Evaluate the TRV breaking capability of the circuit breaker using a two-stage time scale; Described step 4 specifically comprises the following steps: Step 4-1: The time when the circuit breaker TRV reaches the peak value is represented by T ₁ , and the time 20ms after the circuit breaker is disconnected is represented by T _2. The time from the time when the circuit breaker TRV appears to the time when the circuit breaker TRV reaches the peak value is set as the first stage, that is, 0 -T ₁ ; set the time from the peak time of the circuit breaker TRV to 20ms after the circuit breaker is disconnected as the second stage, that is, T ₁ -T ₂ ; Step 4-2: Evaluate the TRV breaking capability of the circuit breaker in the first stage and the second stage respectively; Step 4-3: Conduct a comprehensive evaluation of the breaking capability of the circuit breaker for TRV; Said step 4-2 comprises the following steps: Step 4-2-1: Evaluate the TRV breaking ability of the circuit breaker in the first stage, and obtain the evaluation result of the breaking TRV ability of the circuit breaker in the first stage; specifically: According to the distance from the location of the short-circuit fault in the line with the series compensation device to the circuit breaker, and the collected short-circuit current power frequency effective value of the short-circuit current flowing through the circuit breaker when the short-circuit fault occurs in the line with the series compensation device, According to the TRV test method stipulated in GB1984-2014 "High Voltage AC Circuit Breaker" and GB/Z 24838-2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breaker", when the absolute value of the peak value of the circuit breaker TRV in the first stage and the circuit breaker TRV When the absolute value of the rising rate is not higher than the corresponding specified value in the national standard, it is considered that the TRV of the circuit breaker does not exceed the standard, that is, the breaking TRV capability of the circuit breaker meets the requirements of the first stage; otherwise, the TRV of the circuit breaker is within the first stage. When either the absolute value of the peak value or the absolute value of the TRV rising rate of the circuit breaker is higher than the corresponding specified value in the national standard, it is considered that the TRV of the circuit breaker exceeds the standard, that is, the breaking TRV capacity of the circuit breaker does not meet the requirements of the first stage; Step 4-2-2: Evaluate the TRV breaking ability of the circuit breaker in the second stage, and obtain the evaluation result of the breaking TRV ability of the circuit breaker in the second stage; the details include: Compare the absolute value of the peak value of the circuit breaker TRV in the second stage with GB/T 11022-2011 "GB/T 11022-2011 Standard Common Technical Requirements for High Voltage Switchgear and Control Equipment" and GB/Z 24838-2009 "1100kV High Voltage AC The rated operating impulse withstand voltage of the circuit breaker fracture specified in the Circuit Breaker Technical Specifications, when the absolute value of the peak value of the circuit breaker TRV in the second stage is not higher than the rated operating impulse withstand voltage of the circuit breaker fracture specified in the national standard, It is considered that the TRV of the circuit breaker does not exceed the standard, that is, the breaking TRV capability of the circuit breaker meets the requirements of the second stage; otherwise, it is considered that the TRV of the circuit breaker exceeds the standard, that is, the breaking TRV capability of the circuit breaker does not meet the requirements of the second stage; In the step 4-3, the TRV breaking capability evaluation results of the circuit breaker in the first stage and the TRV breaking ability evaluation results of the circuit breaker in the second stage are integrated according to the logical AND relationship, that is, the TRV breaking ability of the circuit breaker meets the requirements of the first stage , and meet the requirements of the second stage at the same time, it means that the breaking ability of the circuit breaker to break TRV meets the requirements. 2. The circuit breaker breaking TRV capability evaluation method based on two-stage time scale according to claim 1, characterized in that: in the step 1, through electromagnetic transient simulation software simulation or AC electrical quantity test, complete the Acquisition of the power frequency effective value of the short-circuit current flowing through the circuit breaker when a short-circuit fault occurs in the line equipped with a series compensation device. 3. The circuit breaker breaking TRV capability evaluation method based on two-stage time scale according to claim 1, characterized in that: in the step 2, through electromagnetic transient simulation software simulation or high-frequency overvoltage test, complete Acquisition of circuit breaker TRV on lines equipped with series compensation devices. 4. The circuit breaker breaking TRV capability evaluation method based on the two-stage time scale according to claim ₁ , characterized in that: in said step 3, taking the circuit breaker TRV peak time T1 in the national standard as the limit, Analyze the TRV characteristic parameters of the circuit breaker before and after the peak time of the circuit breaker TRV; The characteristic parameters of circuit breaker TRV include peak value, rising rate and time to peak value of circuit breaker TRV. 5. The method for evaluating the breaking TRV capability of a circuit breaker based on a two-stage time scale according to claim 1, characterized in that: in the step 3, for different voltage levels, national standards are used to determine the peak time of the circuit breaker TRV , specifically: for circuit breakers with a voltage level of 126kV ~ 1100kV, the national standards adopted are GB1984-2014 "High Voltage AC Circuit Breakers" and GB/Z 24838-2009 "Technical Specifications for 1100kV High Voltage AC Circuit Breakers". In the test mode, the range of the circuit breaker TRV peak time is 33~3500μs.